This invention relates to deep remediation injection systems for in-situ remediation of contaminated soil and ground water by progressive penetration both vertically and horizontally in contaminated soil and ground water using treatment liquids under high pressure and low volume.
The prior art""s use of biologicals and other treatment materials for soil and water remediation is well-developed but the means of delivery varied widely. For example, some applications have used large boring devices to drill holes in the contaminated soil and set casing into the hole but leave the hole open at the bottom to receive the treatment biologicals for biological remediation. This type of remediation is a very expensive system and very cumbersome and required large equipment. This type of remediation system also does not provide a fine adjustment of the remediation process because it relies upon a few large holes and not many small ones to tightly control the treatment area. This use of drilled holes and set casing also required large drilling equipment to make the holes and large pipe handling equipment to set the pipe in the holes.
Also in the prior art are many other forms of remediation such as the removal of the contaminated soil to be delivered to a treatment site for incineration to burn off the contaminants and leave only clean soil after the process. This has been a very expensive process for remediation and cost is a very important factor in the remediation business. It also can have the pollution side effect of vapor and air pollution while the soil is being removed and moved to the incineration site if not controlled, but the control adds cost to the process also.
Yet other prior art has used biologicals instead of incineration of the hauled off dirt at a remote treatment site in a controlled above ground treatment of the contaminated soil. This approach has many pollution problems such as possible water pollution and air pollution, and is also very expensive. It clearly means handling the soil twice, once on removal and once on completed treatment, just as incineration does.
Most of the prior art was and is designed and used in solo applications and does not work with the other remediation techniques. For example, the removal of contaminated soils to a treatment site for bioremediation of soil would not generally work with or in conjunction with the bored hole and casing approach of bioremediation except in the case of a requirement of double treatment of the contaminated soil.
In one prior art approach to alleviating some of the above-mentioned disadvantages, U.S. Pat. No. 5,868,523, issued Feb. 9, 1999, an in-situ remediation apparatus and method is disclosed using a manually operated soil penetrating lance. The lance has two sets of injection ports spaced widely apart for delivering, respectively, compressed air through one set of ports and a pressurized liquid such as water, hydrogen peroxide, biologicals, surfactants, nutrients or other treatment chemicals for delivery through the other set of ports. Although this approach has advantages over the other prior art approaches, the disclosed soil penetrating lance and the method for using it has been found to have drawbacks. In particular, U.S. Pat. No. 5,868,523 discloses dedication of one set of ports to the compressed gas and the other set of ports to a particular pressurized liquid. In some applications of treating contaminated soils, it is desirable to use at least two different liquids containing distinct chemicals. For example, treatment of contaminated soils by means of the well-known Fenton""s reaction involves use of hydrogen peroxide and a catalyst-containing liquid, which preferably are stored separately and injected into the soil separately. Because U.S. Pat. No. 5,868,523 is adapted only for injection of one liquid stream at a time, intimate mixing of the hydrogen peroxide and the catalyst-containing liquid in the soil in the optimum proportion cannot be assured.
Furthermore, in U.S. Pat. No. 5,868,523, the set of injection ports for the compressed air and the set of injection ports for the pressurized liquid are spaced relatively far from one another. The purpose of spacing the sets of ports relatively far apart is to reduce pressure of the liquid before it comes in contact with the gas ports, to minimize the likelihood of clogging. However, spacing the sets of ports far apart also diminishes the intimacy of the mixing of the gas and/or liquids discharged into the soil from the respective sets of ports.
In U.S. Pat. No. 5,868,523, the lance is built in sections which are connected together using a threaded adaptor nozzle which seals by means of insertion of a male beveled sealing end of a tubular member into a mating female beveled sealing face of the adaptor nozzle. It has been found, however, that this beveled sealing face arrangement may permit leakage between the air conduit and the liquid conduit.
In actual use of the method of U.S. Pat. No. 5,868,523, pressures as high as approximately 3200 psi have been employed. It has been recently discovered, however, that better results are obtained with substantially higher pressures, 3200 to 6000 psi, preferably in the range of 4000 to 6000 psi.
It is the object of this invention to provide an improved in-situ soil and ground water deep injection remediation system for the remediation of contaminated soil and ground water which overcomes the foregoing disadvantages of the prior art.
Also it is an object of this invention to provide a treatment system which permits simultaneous or sequential delivery of two separate streams of different high pressure liquids.
Also it is an object of this invention to provide a treatment system which has two separate sets of discharge ports for different high pressure liquids that are spaced relatively closely to each other.
These and other objects are accomplished in accordance with a preferred embodiment of the present invention providing a deep remediation injection system for in-situ remediation of contaminated soil and ground water capable of progressive penetration both vertically and horizontally in contaminated soil which includes a soil penetrating lance for injecting at least two different highly-pressurized fluids taken from the group of air, gaseous oxygen, ozone, oxygenated liquid, hydrogen peroxide, surfactant-containing liquid, catalyst-containing liquid and suspended biologicals-containing liquids, or a liquid containing other chemicals, into contaminated soil as the soil penetrating lance is inserted for penetration therein, the soil penetrating lance having at least an upper set of injection ports, the upper set of injection ports being generally radially spaced-apart on the lance, and at least one lower set of injection ports, the lance having an average width in the vicinity of upper set of injection ports, the lance including substantially fluidically-independent first and second conduits leading, respectively, to the lower set of injection ports and the upper set of injection ports so as to permit delivery of separate pressurized fluid streams to the upper and lower sets of injection ports and then into the soil, the upper and lower sets of injection ports being spaced apart from each other on the lance a distance no farther than about three times the average width of the lance in the vicinity of the upper set of injection ports.
In accordance with a preferred aspect of this invention, the deep remediation system has the upper and lower sets of injection ports spaced apart from each other a distance no farther than about two times the average width of the lance in the vicinity of the upper set of injection ports.
In accordance with another preferred aspect of the present invention, the radial ports of the lower set of ports of the lance are recessed into a first circumferential groove.
In accordance with another preferred aspect of the invention, the lance further includes a circumferential groove disposed between the radial ports and the axial port of the lower set of ports.
In accordance with another preferred aspect of the invention, the deep remediation system further includes a first selector valve for selectively fluidically connecting the first conduit of the lance to a selected one of at least two fluid sources.
In accordance with another preferred aspect of the invention, the deep remediation system further includes a second selector valve for selectively fluidically connecting the second conduit of the lance to a selected one of at least two fluid sources.
In accordance with another preferred aspect of the invention, the deep remediation system further includes a first selector valve for selectively fluidically connecting the first conduit of the lance to a selected one of at least two fluid sources and a second selector valve for selectively fluidically connecting the second conduit of the lance to a selected one of at least two fluid sources.
In accordance with another preferred aspect of the invention, the lance includes a shaft portion and a fluid injection portion, the fluid injection portion including an upper and lower set of injection ports, the first conduit being co-axial inside the second conduit in at least the shaft portion of the lance.
In accordance with another preferred aspect of the invention, the shaft portion and the fluid injection portion of the lance are removably joinable together, the first conduit being fluidically connectable to the lower set of injection ports and fluidically sealable from the upper set of injection ports by means of a plurality of co-axial O-ring seals.
In accordance with another preferred aspect of the invention, the deep remediation injection system further comprises an adapter tube between the shaft portion and the fluid injection portion, the adapter tube having an upper end including a plurality of co-axial O-rings and being adapted for co-axial insertion into the first conduit in the shaft, and a lower end including a plurality of co-axial O-rings and being adapted for co-axial insertion into a conduit in the fluid injection portion, thereby permitting flow of fluid from the first conduit to the lower set of injection ports and sealable separation of the fluid from fluid in the second conduit leading to the upper set of injection ports.
In another preferred embodiment of the present invention, a method of in-situ deep remediation of contaminated soil and ground water is provided using an injection lance capable of progressive penetration both vertically and horizontally in contaminated soil having an upper set of injection ports and a lower set of injection ports, comprising the steps of connecting a source of highly-pressurized gas to one of the upper and lower sets of injection ports, connecting a source of first highly-pressurized liquid selected from the group consisting of a liquid taken from the group consisting of hydrogen peroxide, liquid containing dissolved ozone, liquid containing dissolved oxygen, liquid-containing suspended biologicals or liquid containing catalysts, liquid containing a surfactant or other chemical, to the other of the upper and lower sets of injection ports, penetrating the lance into the soil to inject the gas and liquid into it through the upper and lower sets of injection ports, disconnecting the source of gas and connecting in its place a source of a second highly-pressurized liquid selected from the group consisting of a liquid taken from the group consisting of hydrogen peroxide, liquid containing dissolved ozone, liquid containing dissolved oxygen, liquid containing suspended biologicals or liquid containing a catalyst, the second highly-pressurized liquid being different from the first highly-pressurized liquid.
These and other and further features and advantages of the present invention, partly schematic, will be apparent to those skilled in the art upon review of the following descriptions and drawings, in which: